The present invention is directed to an apparatus and method of obtaining a sample of fluid from a user for subsequent diagnostic tests.
Capillary blood sampling is a process for obtaining blood samples from the subdermal capillary beds of users. A common method is to produce a small incision in the user""s skin using a sharp needle or small blade, called a blood lancet. See, for example, U.S. Pat. Nos. 6,183,489, 5,554,166, 4,924,879, and Re. 35,803, the disclosures of which are hereby incorporated herein by reference. These existing blood lancets are mostly mechanical devices that use steel lancets to penetrate the skin and damage blood vessels to obtain a blood sample. It is also known to use lasers for perforating materials such as skin tissue. See, for example U.S. Pat. Nos. 6,074,383, 5,947,957, 5,908,416, 5,839,446, and 5,554,153. These existing laser lancets replace the mechanical lancing mechanism through laser perforation of the skin.
Coagulation of bleeding wounds has been used in laser-assisted surgery, such as burn wound removal and surgery on highly-vascularized organs such as the liver for many years. See for example, U.S. Pat. No. 4,273,127, which discloses a cutting and coagulating device for use for relatively bloodless surgery. The laser light penetrates the tissue to deeply coagulate the tissue and produce a clot of sufficient size to allow adequate coagulation, stopping the bleeding.
In addition, lasers have been used to treat congenital vascular malformations, such as port wine stains. See for example, M. J. C. van Gemert et al., xe2x80x9cLaser Treatment of Port Wine Stainsxe2x80x9d, Optical-Thermal Response of Laser-Irradiated Tissue, edited by A. J. Welch and M. J. C. van Gemert, Plenum Press, New York, 1995 (pp789-829). In such a treatment, the laser illumination leads to coagulation of the red blood cells and, by heat conduction, to transmural coagulation of the vessel wall of the ectatic vessel. Ideal wound healing occurs several months later when the ectatic vessels are replaced by one or more xe2x80x9cnormalxe2x80x9d capillaries.
The present invention provides a method and apparatus for obtaining a sample of fluid from a user for diagnostic testing and for sealing the incision following the sampling. The apparatus comprises a housing defining a chamber, a lancet positioned in the chamber and including an end formed to create a fluid collection incision, and a light source positioned in the chamber, the light source formed to emit a light beam of a pre-determined wavelength and for a time sufficient to seal the incision.
According to another aspect of the invention a fluid sampling apparatus is provided. The apparatus comprises a housing defining a chamber, a lancet positioned in the chamber and including an end formed to create a fluid collection incision, means for collecting blood from the open incision, and a light source coupled to the housing, the light source emitting light of a pre-determined wavelength and for a time sufficient to seal the incision following withdrawal of the blood.
According to still another aspect of the invention a method is provided for controlling a fluid collection incision. The method comprises the steps of lancing a portion of skin of a user to create a fluid collection incision, and exposing the fluid collection incision to light having a pre-determined wavelength and for a time sufficient to seal the incision following withdrawal of the blood.
Additional features of the invention will become apparent to those skilled in the art upon consideration of the following detailed description of the preferred embodiment exemplifying the best mode of carrying out the invention as presently perceived.